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**emakarov** Strictly speaking, A \/ B /\ C is not a well-formed formula: it has to be either (A \/ B) /\ C or A \/ (B /\ C). We can drop parentheses only if we make a convention that, say, /\ binds stronger than \/; then A \/ B /\ C would stand for A \/ (B /\ C).

In this problem, the conjunction results from the negation of $\displaystyle ((\neg Px\vee Qx)\rightarrow Qy)$. So,

$\displaystyle \neg Qx\lor\neg\Big((\neg Px\vee Qx)\rightarrow Qy\Big)\equiv\neg Qx\lor\Big((\neg Px\vee Qx)\land \neg Qy\Big)$